Viscose fiber is mainly prepared by using high-purity cellulose dissolving pulp as raw material, which is prepared from cellulose derived from cotton linter, wood and plant straw by a series of processes of acid hydrolysis, alkali hydrolysis, bleaching and others, and by a series of processes of alkali impregnation, pressing, aging, yellowing, dissolving, filtering, spinning, post-processing and others. Ordinary viscose fiber has similar properties with cotton fiber, having wearing comfortability, good hygroscopicity and dyeability, and has advantages which other chemical fibers cannot match. Multifunctional viscose fiber has become one of the hotspots of research, as the consumer has higher and higher requirements on functions of clothing and other materials, such as far infrared, anti-ultraviolet, anti-radiation, anti-static, antibacterial and bacteriostatic functions.
Currently, the prior art discloses a variety of multifunctional viscose fibers. For example, Chinese Patent Application No. 200510104907.3 discloses a silver-containing antibacterial viscose fiber and preparation method thereof, and the method comprises steps of mixing, making glue, spinning, beaming, cutting, refining, drying, packing, and a colloidal solution of nanosilver with a nanoparticle size of 50-65 nm was added during the process of making glue or spinning. The viscose fiber obtained by this method has strong antibacterial, bactericidal and certain anti-static functions. However, this method cannot well solve the problem of agglomeration of nanosilver particles in the process of making glue and spinning, which affects the effect of nanosilver particles. Moreover, in this method, since nanosilver colloidal solution was directly added, although the obtained viscose fiber has bacteriostatic property, other properties such as far infrared, anti-radiation properties and others, are not prominent. Accordingly, the present inventors have considered the preparation of a multifunctional viscose fiber having good far infrared, anti-ultraviolet, anti-radiation, anti-static, bacteriostatic, antibacterial and other functions.